Reference for Chullin 217:4

אימא לא ניער יפה יפה ולא כסה יפה יפה

- Perhaps he did not stir it so well or he did not cover it so well"&gt;.<span class="x" onmousemove="('comment',' And if the pot was not stirred well or covered properly the very moment the drop of milk fell on a piece, that piece would immediately absorb the milk and would render all the contents of the pot forbidden.');">³</span>

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